LSCRPA

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Revision as of 15:03, 25 March 2025 by Kaltakm (talk | contribs) (Created page with "{{TAGDEF|LSCRPA|[logical]|.FALSE.}} Description: {{TAG|LSCRPA}} selects the spectral cRPA method. ---- Selects the spectral cRPA method where following screening effects are subtracted from the full RPA polarizability ::<math>\tilde \chi^\sigma_{{\bf G,G}'}({\bf q},i\omega)\approx \frac 1{N_k}\sum_{nn'{\bf k}} \frac{ f_{n\bf k}-f_{n'\bf k-q} }{ \epsilon_{n{\bf k}} - \epsilon_{n'\bf k-q} - i \ome...")
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LSCRPA = [logical]
Default: LSCRPA = .FALSE. 

Description: LSCRPA selects the spectral cRPA method.


Selects the spectral cRPA method where following screening effects are subtracted from the full RPA polarizability

[math]\displaystyle{ \tilde \chi^\sigma_{{\bf G,G}'}({\bf q},i\omega)\approx \frac 1{N_k}\sum_{nn'{\bf k}} \frac{ f_{n\bf k}-f_{n'\bf k-q} }{ \epsilon_{n{\bf k}} - \epsilon_{n'\bf k-q} - i \omega } \theta_{n\bf k }^{\sigma} \theta_{n'\bf k-p }^{\sigma'} \langle u_{n {\bf k }}^{\sigma } |e^{-i \bf (G+q) r}| u_{n'{\bf k-q}}^{ \sigma' } \rangle \langle u_{n' {\bf k-q}}^{\sigma' } |e^{-i \bf (G'-q)r'} | u_{n'{\bf k }}^{ \sigma } \rangle }[/math]

Here [math]\displaystyle{ \theta_{n{\bf k}}^\sigma }[/math] are the eigenvalues of the correlated projectors [math]\displaystyle{ P_{mn}^{\sigma({\bf k})} = \sum_{i\in \cal T} T_{i m}^{*\sigma({\bf k})} T_{i n}^{\sigma({\bf k})} }[/math] ordered according to their leverage scores. This method results in larger effective interactions compared to w-cRPA or the projector method.

Related tags and articles

LDISENTANGLED, LWEIGHTED, ALGO

Examples that use this tag

References